Switching apparatus



May 3, 1932.

c. w. EBELING SWITCHING APPARATUS Filed April 18, 1950 2 Sheets-Sheet 'l)NVENTOR ATTORNEY Za /es 1 Beg/1y y 1932- c. w EBELING 1,856,09

SWITCHING APPARATUS Filed April 18, 1930 2 Sheets-Sheet 2 INVENTOR BY/Q@ ATTORNEY Patented May 3, 1932 v UNITED STATES PATENT FFEE CHARLES W.EBELING, OF NEW YORK, N. Y., ASSIGNOR TO GENERAL TALKING PICTURESCORPORATION, OF NEW 1 03K, N. Y., A CORPORATION OF DELAWARE SWITCHINGApplication filed April 18,

The present invention relates to improvements in a switching apparatus,one object of the invention being the provision of an apparatus of thistype which is adapted 5 primarily for use in connection with soundon-film apparatus where at least two motion picture projecting machinesare employed, and in which two exciting lamps, one for each machine, arealso employed and where- 10 by, by the manipulation of the switch theloud speakers of the amplifying system are shunted during the periodbetween the cutting out of one eXciter lamp and the cutting in of theother exciter lamp, or vice versa.

Another object of this invention is a provision of a switching device inwhich by the manipulation of a main shaft, a shunting switch is firstoperated and momentarily held in such position during the time that oneele ment is disconnected from a source of electrical energy and untilanother or similar element is connected to said source.

Still another object of this invention is a provision of a device ofthis character which is readily inter-connected between the loudspeakers of an amplifying system and the eX- citer lamps of asound-on-lilm apparatus, thus producing a thoroughly practical andefficient device for this purpose.

\Vith the foregoing and other objects in view, which will appear as thedescription proceeds, the invention resides in the combination andarrangements of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the preciseembodiment of the in: vention herein disclosed can be made within thescope of what is claimed without departing from the spirit of theinvention.

In the accompanying drawings Figure 1 is a view in side elevation of thecomplete frame-work of the present switching apparatus showing the partsin their relative positions.

Figure 2 is a front view thereof.

Figure 3 is a section taken on line 33 of Figure 1 showing an electricaldiagram connected therewith to illustrate one circuit arrangement to becontrolled by the switching apparatus.

APPARATUS 1930. Serial No. 445,451.

Figure eis an enlarged detailed sectional view taken on line 4ll ofFigure 3 showing the switch member in neutral position.

Referring to the drawings, the numeral 5 designates a panel ofinsulating material, there being attached thereto a forward frame-work 6and a front panel 7, while attached to the rear face thereof is a frame8 having a rear plate 9, the whole being so constructed as to be aunitary member.

Journalled in this structure is a main shaft 10 which operates a movablearm 11, which operates in conjunction with an attenuator network orrheostat 11, the detailed construction of which is not herein shown.

Mounted upon the forward end of the shaft 10 external of the casing orframework is an operating disc or knob 12 provided with a pointer orindicator 12, the purpose of which will presently appear. Keyed on andmovable with the shaft 10 within the framework are two discs or cams 13and 14:, the cam 13 being circular throughout the greater portion of itscircumference, but being provided with two periphery teeth 15 and 16. AGeneva member 17 mounted upon a shaft 23 and as particularly shown inFigure 3 is provided with three curved surfaces 18, 19 and 20, whichcoincide with the smooth surface of the cam 13, the surface 19 beingfurther provided with notches or recesses 21 and 22 for the reception atthe proper time of the respective teeth 15 and 16 as the ca n 13 isrotated to oscillate the member 17 and in turn oscillate an arm 24: ofinsulation which in turn carries a metallic shunting switch 25.

It will thus be seen that as the cam 13 is moved in either direction, asfor instance, to the left as viewed in Figure 3 that the tooth 16 willengage the notch 22 and will therefore move the member 17 so that theshunting member 25 thereof would be moved downwardly and that thecontinued movement of the member 13 would cause the tooth to bedisengaged and the surface 20 be brought into sliding contact with thecam 13, so that member 17 will be caused to come to rest. A furthermanipulation of the cam 13 in this particular direction will have noeffect upon the shunting switch 25 but a movement in the oppositedirection will bring the tooth 15 into action and cause the shuntingswitch 25 to be moved in the opposite direction or upwardly.

The cam 14 is for manipulating a modifier Geneva member 27 mounted uponthe shaft 31 and provided with the toothed portion 28 for engagementwith teeth 26 of the cam 14, this member 27 being further provided withthe curved surfaces 29 and 30, which coincide with the smooth curvedsurface of the cam 14. Attached to and for movement with the member 27is an arm 32 of insulating material to which is also connected ametallie switch or arm 33.

In this description it will be noted that when the disc 14 is rotatedclockwise that the teeth 26 would engage the teeth 28 of the member 27and will cause the contact or switch member 33 to be moved upwardlyuntil the surface is brought in contact with the circumference of thecam 14 at which time no further movement will be imparted to the arm 33regardless of the further movement of the member 14, and that to shiftthe arm 33 from its extreme upper position to the extreme lowermostposition the disc 14 is operated counter clockwise so that the teeth 26will act upon the teeth 28 and bring the curved surfaces 30 into contactwith the pe riphery cam, the continued movement of the cam 14 having nofurther eifect upon the member 27.

WVhen the present device is used in connection with a sound amplifyingsystem having the usual amplifiers and loud speakers 41, it is desirablethat no undesirable noise during the switching operation be transmittedthrough the loud speakers and in order to prevent this the shuntingswitch 25 is provided, said switch normally being in contact with therespective contacts 34 or 35 and only being placed in a central orshunting position during the manipulation of the switch 33 and justprevious to the dis-connection thereof from one pair of contacts 44 andor 46 and 47. This shunting action is clearly illustrated in Figure 3causing the contacts 34 and 35 to close the shunt connection 36 and 37to the conductors 38 and 39, and therefore isolate the speakers 41 fromthe amplifiers 40. These respective cont-acts 34 and 35 are attached toand supported from blocks 34 and 35 respectively formed of insulatingmaterial and carried by the panel 5 of the present structure.

Also carried by the panel 5 and at the proper. place thereon are twospaced blocks 42 and 43 of insulating material, which in turn supporttheir respective pairs of spring contacts44 and 45, and 46 and 47,respectively, or as particularly illustrated in Figures 1 and 4. Eitherpair of these contacts are normally engaged by the switch 33 while thenormal position of the switch 25 is in non-bridging relation to thecontacts 34' and 35'.

Briefly stated, one circuit arrangement for controlling the respectiveexciter lamps 51 and 56 is illustrated in Figure 3 and is as follows:

One for the exciter lamp 51 including a battery 48, a conductor 49, thecontacts 46, 33, and 47, a conductor 50, an exciter lamp 51, the groundconnection 52 and the secon ground connection 53.

Vhen the switch 33 is moved to the opposite direction to engage thecontacts 44 and 45, the circuit to energize the exciter lamp 55 includesthe battery 48, the conductor 49, a conductor 54, the contacts 44, 33,and 45, a conductor 55, the exciter lamp 56 and the grounds 57 and 53.

From the foregoing description it is evident that a switching apparatusconnected according to and embodying the present invention willabsolutely eliminate the undesirable noise when making a shift over inthe present universally used type of fadei in scund-on-iilm apparatus,and that during, that particular instant of the cutting out of oneQXCitQI lamp and the cutting in of the second ez-zciter lamp, that theloud speakers in the amplifying system are shunted from the line and aretherefore dead.

As illustrated in Fi -tire 2, the change-over takes place by movement ineither direction of the knob 12 so as to bring the indicator 12 thereofto either zero position, the shunt switch 25 during this movement havingbeen brought into s tinting operation during the change-over of theswitch 33 from one pair of contacts to the other pair and the movementof the shunting switch 25 from bridging or shuntin position to itsneutral position, the continual movement of the knob in that particulardirection, as, for instance, clockwise, as illustrated in Figure 2 beingineffective in its operation of the res )ective switches 25 and 33 buteffective wit relation to the attenuator and according to the dialmarkings 58 or 58 upon the panel 7, the present apparatus being soconstructed that the volume increases from zero to the point of stop, oranywhere within the working range as indicated in Figure 2.

WVhat is claimed is:

1. A switching apparatus including a supporting structure, a main shaftjournalled therein, a shunting switch mechanism mounted therein, aselective switch also mounted therein, a pair of oppositely disposedcooperating switch contacts associated with the latter and adapted to becontacted thereby, one at a time, means for selectively operating themain shaft, two cooperating Geneva movements attached to the main shaftand mounted in the supporting structure whereby the shunting switch isin neutral position and the other switch is in closed position, or viceversa.

2. A switching apparatus including a supporting structure, a main shaftjournalled therein, a shunting switch mechanism mounted therein, aselective switch also mounted therein, a pair of oppositely disposedcooperating switch contacts associated with the latter and adapted to becontacted thereby, one at a time, means for selectively operating themain shaft and twocooperating Geneva movements operably connected to themain shaft, whereby the shunting switch is in neutral position when theother switch is in closed position, or vice versa, following theshunting switch being brought into and held in operation during thedispatch of the other switch from one time to the other.

3. A switching apparatus including a supporting frame, a main shaftmounted therein, a means for selectively operating the main shaft, twocooperating Geneva movements attached to the main shaft and supported inthe framework and a switch under the control of each movement.

4. A switching apparatus including a supporting frame, a main shaftmounted therein, cooperating pointer and dial mechanism for selectivelyoperating said main shaft, two cams mounted upon the main shaft andmovable therewith, two switches, and two Geneva members, one to eachswitch disposed for cooperative operation with the respective cams andso disposed relative thereto that one switch is in neutral position andthe other switch is in closed position, or vice versa.

In testimony whereof I aflix my signature.

CHARLES W. EBELING.

